Brain stem abscesses: cure with medical therapy, case report, and review

European society of Clinical Microbiology and Infectious Diseases guidelines on diagnosis and treatment of brain abscess in children and adults

SCOPE

These European Society of Clinical Microbiology and Infectious Diseases guidelines are intended for clinicians involved in diagnosis and treatment of brain abscess in children and adults.

METHODS

Key questions were developed, and a systematic review was carried out of all studies published since 1 January 1996, using the search terms 'brain abscess' OR 'cerebral abscess' as Mesh terms or text in electronic databases of PubMed, Embase, and the Cochrane registry. The search was updated on 29 September 2022. Exclusion criteria were a sample size <10 patients or publication in non-English language. Extracted data was summarized as narrative reviews and tables. Meta-analysis was carried out using a random effects model and heterogeneity was examined by I2 tests as well as funnel and Galbraith plots. Risk of bias was assessed using Risk Of Bias in Non-randomised Studies - of Interventions (ROBINS-I) (observational studies) and Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) (diagnostic studies). The Grading of Recommendations Assessment, Development and Evaluation approach was applied to classify strength of recommendations (strong or conditional) and quality of evidence (high, moderate, low, or very low).

QUESTIONS ADDRESSED BY THE GUIDELINES AND RECOMMENDATIONS

Magnetic resonance imaging is recommended for diagnosis of brain abscess (strong and high). Antimicrobials may be withheld until aspiration or excision of brain abscess in patients without severe disease if neurosurgery can be carried out within reasonable time, preferably within 24 hours (conditional and low). Molecular-based diagnostics are recommended, if available, in patients with negative cultures (conditional and moderate). Aspiration or excision of brain abscess is recommended whenever feasible, except for cases with toxoplasmosis (strong and low). Recommended empirical antimicrobial treatment for community-acquired brain abscess in immuno-competent individuals is a 3rd-generation cephalosporin and metronidazole (strong and moderate) with the addition of trimethoprim-sulfamethoxazole and voriconazole in patients with severe immuno-compromise (conditional and low). Recommended empirical treatment of post-neurosurgical brain abscess is a carbapenem combined with vancomycin or linezolid (conditional and low). The recommended duration of antimicrobial treatment is 6-8 weeks (conditional and low). No recommendation is offered for early transition to oral antimicrobials because of a lack of data, and oral consolidation treatment after ≥6 weeks of intravenous antimicrobials is not routinely recommended (conditional and very low). Adjunctive glucocorticoid treatment is recommended for treatment of severe symptoms because of perifocal oedema or impending herniation (strong and low). Primary prophylaxis with antiepileptics is not recommended (conditional and very low). Research needs are addressed.

[Successful microsurgical resection of a large brainstem abscess: case report and literature review]

OBJECTIVE

To present a patient with brainstem abscess treated by microsurgical resection.

CASE PRESENTATION

A 53-years-old female patient admitted to the neurosurgical department in a severe condition with symptoms of intracranial hypertension, hyperthermia, general infectious signs and laboratory manifestations of infectious process. Contrast-enhanced MRI revealed a large brainstem lesion (abscess). Retrosigmoid craniotomy with total microsurgical resection of the abscess was performed. External ventricular drainage was incerted on the second postoperative day due to progressive hydrocephalus with clinical deterioration, it was removed in 8 days. Slow positive dynamics was observed in postoperative period. The patient was discharged in 2 weeks after surgery.

CONCLUSION

There are no established algorithm for the treatment of brainstem abscesses. Therapeutic approach is advisable for small abscesses. There are 2 neurosurgical options for this lesion: stereotactic drainage and microsurgical resection with or without external ventricular drainage. Treatment strategy depends on location and size of abscess, as well as clinical state of the patient.

Medullary brain abscess secondary to dental procedure caused by Streptococcus intermedius

Brainstem abscess is an uncommon occurrence in itself and an abscess in the medulla oblongata is even rarer. Although these abscesses have established association with head and neck infections, we report the first known case of medullary abscess that was found to be strongly associated with dental procedure. Important point to note is that a simple procedure like tooth extraction can predispose spread of infective seeding to distant sites. High clinical index of suspicion and early diagnosis are essential, as if left untreated, the brainstem abscess is almost always fatal otherwise.

Brainstem abscess treated conservatively

Background:

Brainstem abscess is a rare condition with a variety of treatment approaches. In this paper, we report an unusual case of a brainstem abscess with a positive outcome in an immunocompetent patient who was treated with antibiotic therapy.

Case Description:

A 22-year-old female presented with bilateral tetraparesis that was worse on the left hemibody, appendicular tremor, and left upper eyelid ptosis. Brain magnetic resonance imaging showed an abscess in the pons and midbrain due to possible nocardiosis. She was treated with dexamethasone, phenytoin, vancomycin, and meropenem for 8 weeks and trimethoprim-sulfamethoxazole for 6 weeks. The brain injury decreased, and the patient’s neurological status significantly improved.

Conclusion:

Brainstem abscess may be treated conservatively, leading to improvement of the clinical condition and decreased lesion size on imaging.

Brain and Spinal Epidural Abscess

PURPOSE OF REVIEW

Brain abscesses and spinal epidural abscesses are serious, potentially life-threatening infections of the central nervous system. This article outlines the clinical presentation, evaluation, and management of brain abscesses and spinal epidural abscesses, with a specific focus on bacterial infections.

RECENT FINDINGS

The overall incidence of brain abscesses has declined, in part because of fewer brain abscesses associated with otogenic infections. However, emerging patient populations at high risk for brain abscess include those with a history of penetrating head trauma, neurosurgery, or immunodeficiency. Improved mortality rates for brain abscess are attributable to modern diagnostic imaging, stereotactic-guided aspiration, and newer antimicrobials that readily penetrate into the central nervous system and abscesses. Brain MRI is more sensitive than CT for brain abscess, particularly in the early stages, but CT remains more widely available and can adequately identify potential abscesses and confirm response to treatment. With the advent of minimally invasive neurosurgical techniques, surgical excision is often employed only for posterior fossa, multiloculated, or superficial well-circumscribed abscesses. In select clinical scenarios, conservative medical management may be a safe alternative to a combined surgical and medical approach. Unlike brain abscess, the incidence of spinal epidural abscess is on the rise and has been attributed to higher prevalence of predisposing factors, including spinal procedures and instrumentation.

SUMMARY

Successful diagnosis and management of brain abscess and spinal epidural abscess requires a collaborative approach among neurologists, neurosurgeons, radiologists, and infectious disease physicians. The foundation of management of brain abscess includes surgical intervention for diagnostic purposes if a pathogen has not been identified or for decompression of larger abscesses or those with mass effect and significant surrounding edema; appropriate dosing and adequate duration of an antimicrobial regimen tailored to the presumptive source of infection and available culture data, and eradication of the primary source of infection. For spinal epidural abscesses, neurologic status at the time of presentation is directly related to outcomes, underscoring the importance of prompt recognition and intervention.

Neuroimaging in Central Nervous System Infections

Radiologic imaging is often employed to supplement clinical evaluation in cases of suspected central nervous system (CNS) infection. While computed tomography (CT) is superior for evaluating osseous integrity, demineralization, and erosive changes and may be more readily available at many institutions, magnetic resonance imaging (MRI) has significantly greater sensitivity for evaluating the cerebral parenchyma, cord, and marrow for early changes that have not yet reached the threshold for CT detection. For these reasons, MRI is generally superior to CT for characterizing bacterial, viral, fungal, and parasitic infections of the CNS. The typical imaging features of common and uncommon CNS infectious processes are reviewed.

From Diagnostic Imaging to Management of Bacterial Brain Abscesses

Advances in neuroradiological investigation have revolutionised the diagnosis and treatment of brain abscesses. CT and MR scans offer diagnostic information, disclosing the exact location, morphology and stage of infection. When these examinations fail to define the type of lesions, nuclear medicine can be called into play with scintigraphy using labelled autologous leukocytes performed with SPECT for differential diagnosis.

Once the diagnosis of brain abscess is established, management is based on neuroradiological findings such as abscess stage, size, localisation and number and clinical information such as source of infection and the general clinical conditions of the patient. Conservative management is confined to small lesions at the early stage in patients whose general clinical condition is good and stable and there are no signs of intracranial hypertension. Surgery is required to treat large abscesses when the patient's general condition is poor. Different procedures are available, endoscopic evacuation aided by stereotactic systems now being the method of choice with respect to traditional excision. Neuroradiological monitoring is necessary whatever the treatment option to assess outcome and possible recurrence.

Brain abscesses: management and outcome analysis in a series of 84 patients during 12 year period

Authors analyze 84 cases of brain abscesses operated between January 2000 and December 2011, in the Fourth Neurosurgical Department by the same surgical team. We underline the general series profile: the mean age was 42.96 years (range: 11-75 years old), 72.62% were males, association with heart defects in seven cases (8.33%), positive bacteriological examination for germs in only 37 cases (44.04%), all negative for HIV infection. The median number of days to diagnosis was 9. Most frequent clinical presentations included headache (40.47%), fever (35.71%), focal neurologic deficits (29.76%), increased intracranial pressure (28.57%) and seizures (11.90%).

The majority of cases (76.19%, n=64) presented a supposed medical condition favoring dissemination of a previous infection: malnutrition, tuberculosis, chronic alcoholism, chronic liver malady, neglected dental or ear infections, and only 5 cases (5.95%) had been diagnosed with secondary immunodeficiency syndromes following autoimmune systemic diseases.

According to our treatment policy all cases except for two (treated by puncture and aspiration) benefited of open surgery and total removal of the lesions, without local recurrence. Outcome was favorable in 82.14% (n=69) of subjects. General morbidity was 26.19%, and mortality stood at 7.14%. Six cases remained with permanent motor deficit (7.14%) and four (4.76%) with controllable seizures. Out of a total of 33.33% (n=28) of complications, 64.28% were due to medical causes.

Follow-up had been extended up to three years for at least 2/3 of patients, who resolved in time medical or surgical conditions which determined cerebral dissemination of the infection. Despite of a poor medical and biological condition, the patients with brain abscess outside of HIV infections benefit from neurosurgical adequate treatment, and if supportive medical and general therapy is continued and sustained, the healing and survival in good neurological status is the rule. Hematogenous spread and advance age were predictors of poor prognosis. Our findings are similar to the results of recent works, although in our series, there is a higher frequency of aerobe germs

Rhomboencephalitis caused by Listeria monocytogenes

Listerial rhomboencephalitis is a rare, devastating treatable disease. A previously well 72-year-old man presented with a one-week history of fever and headache. Four days before admission he developed right facial numbness and ataxia. Diagnosis and treatment are described, including the relevant clinical, laboratory and radiological findings.

Supratentorial and infratentorial brain abscesses: surgical treatment, complications and outcomes--a 10-year single-center study

OBJECTIVE

To analyze the variables determining morbidity, mortality and outcome in subjects with brain abscesses treated at a single center over a 10-year period.

METHODS

A retrospective study was conducted on a series of 59 patients with brain abscesses surgically treated with stereotactically guided aspiration or open craniotomy excision. Such variables as age, gender, clinical presentation, number of days to diagnosis, location, number of lesions, predisposing factors, mechanism of infection, etiological agent, and therapy were analyzed independently. Complications were defined as any deviation from the normal postoperative course occurring within 30 days of surgery, and classified according to a four-point gradual severity scale. Postoperative outcome was appraised through the Glasgow Outcome Scale (GOS) 6 months after surgery, 0-4 points were considered poor outcome and 5 points good outcome.

RESULTS

Eighty abscesses were diagnosed and surgically managed in 59 patients. The mean age was 44.69 years (range: 0.16-77); 59.3% were female. The median number of days to diagnosis was 7. Most frequent clinical presentations included fever (52.5%), headache (42.4%), and focal neurologic deficits (39%). Mechanism of infection was mainly hematogenous spread (32.2%). Stereotactically guided aspiration was the treatment of choice for 74.6% of the patients, whereas 25.4% of the cases were managed through open craniotomy excision. Outcome was favorable in 81.35% (n = 48) of the subjects. General morbidity was 27.1%, and mortality stood at 10.16%. Out of a total 38.98% (n = 23) of complications, two-thirds were due to medical causes. The analysis of variables revealed that only age (p = 0.02), immunosuppression (OR 5.83; p = 0.012) and hematogenous spread (p < 0.01) were associated with poor outcomes.

CONCLUSIONS

Immunosuppression, hematogenous spread and advanced age were predictors of poor prognosis. Most of the complications following brain abscess management were not directly related to surgery or surgical technique.

The experiences of non-operative treatment in patients with bacterial brain abscess

Although treatment of brain abscess requires a combination of antimicrobials and surgical intervention for the infected foci, nonsurgical, empirical treatment is possible and efficient in selected groups of patients. A total of 31 patients were enrolled in this 22-year retrospective study. We describe our therapeutic experiences and attempt to analyze the risk factors that were predictive of therapeutic outcomes. Multiple logistic regression was used to evaluate the relationships between baseline clinical factors and therapeutic outcome during the study period. Of these 31 patients, 25 had community-acquired infections, whereas the other six had nosocomially-acquired infections. Thirteen cases (42%) had a single brain abscess and the other 18 cases (58%) had multiple brain abscesses. Furthermore, the association of bacterial meningitis and brain abscess was found in 81% (25/31) of cases. The overall case fatality rate was 48% (15/31). Significant risk factors for poor outcomes included Glasgow coma scale (GCS) at presentation, presence of septic shock and neck stiffness. In addition, each reduction of one point on the GCS increased the poor outcome rate by 28%. The findings of the study demonstrate that both a higher mortality rate (48%) and worse outcomes were found in this select group of patients. Among the significant prognostic factors, a lower mean GCS at presentation was a major determinant of poor outcome.

Idiopathic pontine Streptococcus salivarius abscess in an immunocompetent patient: management lessons through case illustration and literature review

A 55-y-old woman with no previous medical history presented with a 3-day history of progressive headache, nausea, emesis, right-sided facial numbness, and right-sided extremity weakness. Serial magnetic resonance imaging demonstrated rapid enlargement of a left-sided ring-enhancing dorsal pontine lesion with an exophytic portion, raising concern for an abscess. A stereotactically guided left-sided retrosigmoid craniotomy for abscess incision and decompression was performed given the rapid progression of her neurological deficits. Streptococcus salivarius was isolated from the intra-operative samples. After an extensive evaluation, no source for the S. salivarius was identified. Solitary brainstem abscesses are uncommon intracranial infections with high morbidity and mortality. Patients can present with non-specific symptoms and often have no previous medical history. Since 1974, 40 patients with solitary brainstem abscess have survived to hospital discharge. We outline management strategies for solitary brainstem abscess based on a literature review of survivors.

Abscess of the Medulla Oblongata in a Toddler: Case Report and Technical Considerations Based on Magnetic Resonance Imaging Tractography

BACKGROUND AND IMPORTANCE:

We report a unique case of a toddler (the only one reported) successfully operated on for a medulla oblongata abscess and comment on the influence of neuroimaging modalities in the preoperative planning of the surgical approach.

CLINICAL PRESENTATION:

We report a case of a 20-month-old child with a solitary medulla oblongata abscess. The abscess appeared to be in close proximity to the anterior medulla oblongata, but preoperative planning based on diffusion tensor imaging (DTI) tractography motivated us to try to remove this lesion through a midline suboccipital approach. The ventral medulla oblongata abscess was surgically removed via a telovelar approach. At the anterior wall of the 4th ventricle, a fenestration was made with pus release and evacuation of the cavity. The child was discharged 1 week later with an uneventful and full recovery.

CONCLUSION:

Modern imaging modalities of the nervous system can be very helpful in preoperative planning. Functional visualization of the nervous system provided by modern imaging techniques, such as the DTI tractography, can alter the classic topographic concept of surgical approach. In the case presented, approaching an anterior medulla oblongata abscess based on DTI tractography data, through a suboccipital midline transventricular approach, proved to be an effective and safe technique.

Brainstem abscess caused by Haemophilus influenza and Peptostreptococcus species

We present a patient with a solitary brainstem abscess caused by Haemophilus influenza type b (Hib) and Peptostreptococcus species. This is the first report of a Hib brainstem abscess in the English literature. Hib has been mainly associated with respiratory or nasal infections, and a few cases of intracerebral abscesses, but no brainstem abscesses have been described. The literature on solitary brainstem abscesses was reviewed and an overview of the literature between January 1984 and May 2009 is presented.

Management of brain abscesses in children

Brain abscesses occur infrequently but continue to be problematic for the pediatric neurosurgical community. The incidence of brain abscesses in children has not changed much, although individual reports may show an increase or decrease in the number of reported cases depending on the patient population studied. An increase could be attributed to earlier detection due to advancements in imaging modalities and/or to an increase in the number of children with immunodeficient states caused by AIDS, chemotherapy for malignant lesions, and immunosuppressive therapy for organ transplantation. A decrease in the incidence of brain abscesses could be attributed to practices such as antibiotic treatment for otitis media, sinusitis, and/or prophylactic antimicrobial treatment for congenital heart disease in children. The morbidity and mortality rates associated with brain abscesses have not changed dramatically in the antibiotic and imaging era, and their preferred management can vary among healthcare providers. These lesions have been successfully treated by neurosurgeons. The causes of brain abscesses are highly variable in children, which is also the case in adults, but the predisposing factors in the pediatric population differ in prevalence. Cyanotic congenital heart disease, hematogenous dissemination, contiguous infection, and penetrating traumatic injuries are the most common causes of brain abscesses in children. In this review, the authors discuss the causes and medical and surgical management of brain abscesses in children.

Brain abscess: clinical aspects of 100 patients

OBJECTIVE

To verify if, in the last two decades, there have been any changes in epidemiological, clinical, diagnostic, therapeutic and prognostic aspects of patients with brain abscess.

METHOD

We studied retrospectively 100 patients discharged over a 17-year period from Ca' Foncello Regional Hospital, Treviso, Italy with a diagnosis of brain abscess.

RESULTS

Post-surgical abscesses were more frequent than those related to contiguous infections and the spectrum of etiologic agents was very heterogeneous. A cerebral neoplasm was the initial neuroradiological diagnosis in 13 patients; 72 patients underwent a neurosurgical procedure. A comatose state at presentation was associated with an unfavourable outcome.

CONCLUSION

With the exception of some epidemiological aspects, which varied from the literature, in spite of the improvements in diagnostic procedures and treatment, no significant changes occurred in the prognosis of patients with brain abscess.

Brain stem abscesses in childhood

BACKGROUND

Solitary brain stem abscess is a rare condition with high mortality and morbidity. These lesions were considered to be invariably fatal before 1974 when advanced diagnostic tools were not available. Recently, the diagnosis and prognosis of brain stem abscesses have been modified by the introduction of modern radiological tools, and several patients with a favorable outcome have been reported since then. Because the pons is the most common site of the abscesses, involvement of the sixth and seventh nerves is frequent. The midbrain is the second most likely location, and medullary abscesses are distinctly rare. Treatment of a brain stem abscess includes medical therapy alone, open microsurgical intervention, or stereotactic aspiration.

CASE REPORT

We report a case of a 7-year-old girl with a solitary brain stem abscess. Her neurological examination revealed involvement of the cranial nerves and pyramidal tracts. Microsurgical exposure and aspiration of the abscess resulted in rapid improvement in her neurological condition and radiological resolution of the lesion. We discuss this uncommon case to draw attention to the importance of early diagnosis and adequate treatment, and we review the relevant literature.

Brain abscess in children

Brain abscess is a relatively uncommon but life-threatening infection in children. It can originate from contiguous site infections (eg, chronic otitis media, mastoiditis, sinusitis, meningitis), from distant pathologic states (eg, cyanotic congenital heart disease, chronic lung infections), after head trauma or neurosurgical procedures, or from cryptogenic sources. Predominant etiologic microorganisms vary depending on these predisposing factors. Computed tomography and magnetic resonance imaging are essential tools that enable the physician to make an accurate diagnosis of intracranial purulent collections. Proper selection of antimicrobial agents with good penetration of the central nervous system and with adequate coverage of both anaerobic and aerobic bacteria is critical for the medical management of brain abscess. Delay in surgical drainage can be associated with high morbidity and case-fatality rates. In the early phase of cerebritis, however, infection can respond to antibiotic therapy alone. Advances in diagnostic and therapeutic modalities during the last decade have improved the prognosis of this serious disease.

Brain-stem abscess successfully treated by microsurgical drainage: a case report

Brain-stem abscess is an uncommon condition associated with high mortality. The best method of treatment is not yet defined. It can be managed by medical treatment alone, stereotactic aspiration of the pus and medical treatment, or surgical excision/drainage of the abscess. We present a case of large brain-stem abscess, treated successfully by surgical drainage after the failure of medical treatment. The patient had a large brain-stem abscess extending from the mid-brain down to the lower pons. She was in a poor neurological condition pre-operatively, and was worsening despite intravenous antibiotics. The abscess was coming close to the surface in the lateral aspect of the mid-brain. The presumed source of infection was multiple dental abscesses. The brain-stem abscess was approached by a subtemporal transzygomatic approach and drained completely after making an incision on the lateral surface of the mid-brain. After the operation, the patient showed steady improvement. At six months after the surgery, the patient was fully conscious, talking fluently, and walking with the help of a walker. Her hemiparesis and co-ordination were improving. Surgical drainage of a brain-stem abscess is indicated when medical therapy fails. Proper anatomical knowledge of the brain-stem and the selection of appropriate surgical approach is important for safe drainage of the abscess.

Brain abscesses caused by oral infection

Brain abscesses are rare but can be life-threatening infections. Recent progress in microbiological classification and identification has indicated that they are sometimes caused by oral infection and dental treatment. It has been postulated that oral microorganisms may enter the cranium by several pathways: 1) by direct extension, 2) by hematogenous spread, 3) by local lymphatics, and 4) indirectly, by extraoral odontogenic infection. In the direct extension, oral infections spread along the fascial planes. Hematogenous spreading occurs along the facial, angular, ophthalmic, or other veins which lack valves, through the cavernous sinus and into the cranium. Another hematogenous pathway is through the general circulation. Oral bacteria may cause systemic infections, e.g., endocarditis, and then indirectly initiate brain abscess. Microbiota, complications, and the prevention and management of odontogenic brain abscesses are also discussed in this review.

Focal intracranial infections

Focal intracranial infections are relatively rare, but the consequences of a missed or delayed diagnosis are significant. The clinician is urged to consider these diagnoses in patients with headaches or focal neurologic examinations, particularly in the setting of known or suspected otorhinologic disease. For diagnosis, gadolinium-enhanced MR imaging or MR imaging with angiography are the procedures of choice; CT is far less sensitive and specific. Lumbar puncture is contraindicated in most of these infections. Management of suspected elevation of intracranial pressure and broad empiric antibiotic therapy should be instituted emergently. Early involvement of surgical services is recommended.